Spiral covering machine



sept. 13, 1938.

c. T. PASTOR SPIRAL COVERING MACHINE Filed Nov. 11, 19.56

Patented Sept. 13, 1938 UNITED STATES PATENT OFFICE v 2,129,956 sPmAL covEmNG MACHINE Carl Theodor Pastor, Huls, near Krefeld,

Germany Application November 11, 193s, serial No. 110,32

In Germany October 27, 1934 s claims. (ci. 117-42) My invention relates to a spiral covering machine with spindles having individual electric drives.

When covering threads, the core threadpassaxial direction, thereby impairing the quality of` and secured to thel upper end of the spindle revolving at a speed exceeding 6,000 R. P. M. At such a high speed, the air is centrifugated from the outer'edge of the thread guide, thus causing by the depression thereby produced a supplementary air current in a substantially axial direction which then flows from the center Aof the calotte to the periphery thereof. 'I'his air current presses the covering thread running 'on the core thread against the surface ofthe calotte. In this manner, a wandering of the point where the covering thread runs on the core thread moving in the axial direction is prevented. The air current is strengthened according to the invention by a stationary ring arranged above the'upper end of the bobbin and having a convex surface with respect to the axis of the spindle. In

operation the ring influences the air current in the neighborhood of the. covering thread. The revolving covering thread doesI not, however, come into contact with the ring.

' In the accompanying drawings two embodiments of my invention are vshown in diagrammatic form, in which Fig. 1 shows an elevational view of a spiral covering machine and Figs. 2 and 3 show a modied form of the invention.

'I'he motor I carries on its hollow spindle the thread holding bobbin 2. The thread to be covered, for instance, a rubber thread 4 passes through the hollow spindle 3. The mushroomshaped thread guide 5 adapted to the form of the thread balloon is secured to the upper end of the hollow spindle 3 so as to directly face the running-on point of the cover thread. 6 denotes the ring which strengthens the air current pro- 66 duced. The thread balloon 'l assumes the shape as indicated at 1 or 'l' depending upon Whether the thread runs oi from the lower or upper end' of the bobbin 2.

The essential feature ofthe invention lies, consequently, in the fact that the thread 1 isi pressed 5 onto the revolving calotte 5 by the air current coming from above as indicated `by tli'e arrows 8. The ring 6 has a nozzle-like effect. The air current is produced according to the embodiment u shown in Fig. 1 by the revolving calotte from the 10 i edge of which the air is centrifuged thus creating a depression, whereby a supplementary aircurrent is produced a's indicated bythe arrows 8 which presses the thread onto the calotte. The calotte, therefore, fulfills at the same time two 15 requirements, i. e., it serves to guide the thread and to produce the air current.

The invention is not limited tothe embodiment disclosed, particularly not to the means described for guiding the thread and for producing the air 20 current.

'I'he device shown in' diagrammatic form in Figs. 2 and 3 serves to strengthen the air current which presses the` covering thread onto the calotte. This is brought aboutv by longitudinal 25 apertures arranged in the bobbin holding the covering thread. 'I'hese longitudinal apertures have a fan-like eiect, since owing to the high speed of the bobbin the air present in the longitudinal apertures is caused to flow outwardly and, there- 30 fore, in the downward direction out of the bores of the bobbin. 'Ihe depression thereby created in the bores of the bobbin causes a suction of the air in the axial direction. This current of air pas'ses along the covering thread and presses 35 the latter firmly against the surface of th'e mushroom-shaped ,thread guide. For strengthening the air current a circular cover plate which has fan-like acting projections, recesses or inclined perforations or any suitable means 40 for producing a fan effect maybe preferably arranged on the upper end of thethread holding bobbin. This eect may be further strengthened by giving the inner surface of the longitudinal apertures a convenient shape by providing these 45 'surfaces with grooves or the like which under circumstances have such a twist as to act as an axial pump. Other means such as devices which are based on the principle of the Francis turbine'or the Kaplan turbine or also other blade 50 wheels and the like may be employed for l strengthening the air current.

It has been found particularly advantageous to design spiral covering devices each combined with an electric motor in such a manner that the air current produced by the motor-ventilator is utilized for influencing the run of the thread. 'I 'he means forproducing the air current are so designed that the air current is regulable.

In Fig. 2, 2l denotes the thread passing through the hollow spindle and which is to be covered with the thread 22. 23 is the running-on point, 24 is4 the motor, 25 the spindle thereof and 26 the bobbin mounted thereon. The body of the bobbin has longitudinal bores 21. denotes a plate or cover mounted on the upper frontal side of the bobbin 26 and gripping over the rim 33 of this bobbin. 'I'he cover 34 has openings and projecting parts 35, thus forming a fan for producing an air current which passes the bores 21. The direction of the air current is indicated by the arrows 28. The mushroom-shaped thread guide 29 adapted to the thread balloon is provided with a hole 30 for the passage of the thread 2| to be covered. 3| denotes the covering yarn on the bobbin.

Fig. 3 illustrates a plan View of the bobbin having a hub 3.2 as shown.

The machine according to the invention may be under circumstances employed also for twisting when the core threadto be covered is omitted.

I claim as my invention:

1. In a machine for twisting cover threads around a core thread, a rotatable tubular spindle for guiding the core thread, means for holding a bobbin of the cover thread, a thread guide fixedly mounted on one end of said spindle for guiding said cover thread coming from said bobbin around said core thread, said machine being designed to allow, when in operation, said cover thread to form a thread balloon, said thread guide having a guidingsurface adapted to the shape of the adjacent part of said balloon, and a stationary ring arranged between said bobbin and said thread guide and having a convex inner annular surface in order to guide the air current produced by said thread guide and said balloon when in operation, said ring surrounding -said spindle concentrlcally and the diameter of the portion of theI inner ring surface nearest to said balloon being larger than the diameter of the balloon portion next adjacent to said ring surface,

2. In a machine for twisting cover threads around a core thread, a tubular spindle designed to carry a bobbin of said cover thread and to guide through its bore said core thread, an electric motor connected with said spindle and adapted for revolving said spindlev at a speed above 6,000 R. P. M., a mushroom-shaped guide for said cover thread mounted `on one end of said spindle, means, actuated by said spindle, for producing an air currentl flowing in axial direction against said thread guide, and a body for holding a bobbin of said cover thread, said body being arranged on said spindle between said motor and said thread guide and having apertures in axial direction for the passage of said air current, said machine beingdesigned to allow, when in operation, said cover thread to form a thread balloon, and said thread guide having a guiding surface adapted to the shape of the adjacent part of said balloon.

3. In a machine for twisting cover threads around a core thread, a tubular spindle designed to carry a bobbin of said cover thread and to guide through its bore said core thread, an electric motor connected with said spindle and adapted for revolving-said spindle at a speed above 6,000-R. P. M., a mushroom-shaped guide for said cover thread mounted on one end of said spindle, a body for holding a bobbin of said cover thread, said body being arranged on said spindle between said motor and said thread guide and having longitudinal apertures for the passage of air, and a fan-like element on said body for producing an air current flowing'in axial direction against said thread guide and partly passing through said apertures of said body.

4. In a machine for twisting cover threads around a core thread, a tubular spindle designed to carry a bobbin of said cover thread and to guide through its bore said core thread, an electric motor connected with said spindle and adapted for revolving said spindle at a speed above 6,000 R. P. M., a mushroom-shaped guide for said cover thread mounted on one end of said spindle, means for holding a bobbin of said cover thread on said spindle between said motor and said mushroom-shaped guide, said machine being designed to allow, when in operation, said cover thread to form a thread balloon, said thread guide havinga convex surface shaped according to the contour of the-adjacent portion of said thread balloon and being arranged to Ycontact with said portion.

5. In a machine for twisting strands from threads, a revolvable spindledesigned for carry- `to hold said thread in contact with said surface,

said machine being designed to allow, when in operation, said cover thread to form a thread balloon, and said thread guide having a guiding surface adapted to the shape of the adjacent part of said balloon.

6. With a machine for twisting cover threads around a core thread, said machine being designed to allow said cover thread to form a thread balloon, in combination, a rotatable tubular spindle for guiding said core thread, means for holding a bobbin of said cover thread, and a rotatable thread guide xedly mounted on the end of` said spindle so as to be in immediate proximity of the running-on point of said cover thread, said thread guide having a convex surface shaped according to the contour of the adjacent portion of said thread balloon and being arranged to contact with said portion.

CARL THEODOR PASTOR. 

